Medicament delivery device and cartridge

ABSTRACT

Described is a cartridge ( 200 ) comprising a body ( 205 ) adapted to contain a medicament, a bung ( 210 ) slidably disposed in the body ( 205 ) and having a distal face ( 215 ) and a proximal face ( 220 ), and a light element ( 225 ) coupled to a component of the cartridge ( 200 ). Further described is a medicament delivery device ( 100 ) comprising the cartridge ( 200 ), a first receiver ( 110 ) adapted to receive an optical signal from the light element ( 225 ) and convert the optical signal into a first electrical signal, and a second receiver ( 115 ) adapted to receive an optical signal from the light element ( 225 ) and convert the optical signal into a second electrical signal.

TECHNICAL FIELD

The invention relates to medicament delivery device and a cartridge.

BACKGROUND OF THE INVENTION

Administering an injection is a process which presents a number of risksand challenges for users and healthcare professionals, both mental andphysical. Injection devices typically fall into two categories—manualdevices and autoinjectors. In a conventional manual device, manual forceis required to drive a medicament through a needle. This is typicallydone by some form of button/plunger that has to be continuously pressedduring the injection.

Autoinjector devices aim to make self-injection easier for patients. Aconventional autoinjector may provide the force for administering theinjection by a spring, and trigger button or other mechanism may be usedto activate the injection. Autoinjectors may be single-use or reusabledevices.

Conventional autoinjectors have limited safety features and compliancefeatures. For example, some conventional autoinjectors may continuedispensing the medicament even when the autoinjector is removed from theinjection site. Thus, it cannot be determined whether the patientreceived an intended dose.

Conventional delivery devices may also have limited feedback mechanisms.For example, some conventional delivery devices may provide audiblefeedback only, when an injection is initiated and/or completed.

Conventional injection devices may deliver the entire contents of asyringe/cartridge or may provide a predetermined or set dose.Conventional injection devices can lack mechanisms to ensure accuratedose delivery. For example, when the entire contents of thesyringe/cartridge are intended to be delivered, a residual amount mayremain which either means that a full dose was not delivered or thesyringe/cartridge must be overfilled to ensure a proper dose isadministered. As a further example, when the predetermined/set dose isdelivered, over- or under-dosing may occur.

Thus, there remains a need for an improved medicament delivery deviceand cartridge.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an improvedmedicament delivery device and cartridge.

In an exemplary embodiment, a cartridge according to the presentinvention comprises a body adapted to contain a medicament, a bungslidably disposed in the body and having a distal face and a proximalface, and a light element coupled to a component of the cartridge.

In an exemplary embodiment, the light element is coupled to the proximalface of the bung. The light element is wholly or partially embedded inthe bung.

In an exemplary embodiment, the light element is coupled to the body.

In an exemplary embodiment, the cartridge further comprises a powersource electrically, inductively or radio frequency coupled to the lightelement.

In an exemplary embodiment, the light element is a light emitting deviceor a light reflecting device.

In an exemplary embodiment, the bung is translucent or made of a lightreflecting material.

In an exemplary embodiment, the cartridge further comprises a lensdisposed adjacent the light element.

In an exemplary embodiment, a medicament delivery device according tothe present invention comprises the cartridge, a first receiver adaptedto receive an optical signal from the light element and convert theoptical signal into a first electrical signal, and a second receiveradapted to receive an optical signal from the light element and convertthe optical signal into a second electrical signal.

In an exemplary embodiment, the delivery device further comprises alight source disposed adjacent the first receiver and the secondreceiver. The light source is adapted to emit light toward the lightelement.

In an exemplary embodiment, the first receiver and the second receiverare radially offset by a radial distance from a longitudinal axis of thedelivery device.

In an exemplary embodiment, the first receiver and the second receiverare axially offset by an axial distance.

In an exemplary embodiment, the first receiver is arranged a firstminimum axial distance from a reference line and the second receiver isarranged a second minimum axial distance from the reference line. Thereference line corresponds to an axial position of the light elementprior to use of the medicament delivery device.

In an exemplary embodiment, the delivery device further comprises acontroller adapted to compute a displacement of the light elementrelative to the reference line using the first and second electricalsignals. The controller is adapted to compute a dose of medicamentdelivered or a needle position based on the displacement. The controllercomputes the displacement as follows:

$I = \left\lbrack \frac{r_{1} - r_{2}}{\left( {\sqrt{\frac{\cos \; \alpha}{E_{1}}} - \sqrt{\frac{\cos \; \alpha}{E_{2}}}} \right)} \right\rbrack^{2}$$r = \sqrt{\frac{I*\cos \; \alpha}{E_{1}}}$

where E1 illumination value at first receiver;

-   -   E2 illumination value at second receiver;    -   I total illumination;    -   α angle of diffusion of light from the light element relative to        the longitudinal axis;    -   r displacement of light element relative to the reference line;    -   r1 first minimum axial distance between the light element and        the first receiver when the light element is positioned at the        reference line; and    -   r2 second minimum axial distance between the light element and        the second receiver when the light element is positioned at the        reference line.

The term “drug” or “medicament”, as used herein, means a pharmaceuticalformulation containing at least one pharmaceutically active compound,

wherein in one embodiment the pharmaceutically active compound has amolecular weight up to 1500 Da and/or is a peptide, a proteine, apolysaccharide, a vaccine, a DNA, a RNA, an enzyme, an antibody or afragment thereof, a hormone or an oligonucleotide, or a mixture of theabove-mentioned pharmaceutically active compound,

wherein in a further embodiment the pharmaceutically active compound isuseful for the treatment and/or prophylaxis of diabetes mellitus orcomplications associated with diabetes mellitus such as diabeticretinopathy, thromboembolism disorders such as deep vein or pulmonarythromboembolism, acute coronary syndrome (ACS), angina, myocardialinfarction, cancer, macular degeneration, inflammation, hay fever,atherosclerosis and/or rheumatoid arthritis,

wherein in a further embodiment the pharmaceutically active compoundcomprises at least one peptide for the treatment and/or prophylaxis ofdiabetes mellitus or complications associated with diabetes mellitussuch as diabetic retinopathy,

wherein in a further embodiment the pharmaceutically active compoundcomprises at least one human insulin or a human insulin analogue orderivative, glucagon-like peptide (GLP-1) or an analogue or derivativethereof, or exendin-3 or exendin-4 or an analogue or derivative ofexendin-3 or exendin-4.

Insulin analogues are for example Gly(A21), Arg(B31), Arg(B32) humaninsulin; Lys(B3), Glu(B29) human insulin; Lys(B28), Pro(B29) humaninsulin; Asp(B28) human insulin; human insulin, wherein proline inposition B28 is replaced by Asp, Lys, Leu, Val or Ala and wherein inposition B29 Lys may be replaced by Pro; Ala(B26) human insulin;Des(B28-B30) human insulin; Des(B27) human insulin and Des(B30) humaninsulin.

Insulin derivates are for example B29-N-myristoyl-des(B30) humaninsulin; B29-N-palmitoyl-des(B30) human insulin; B29-N-myristoyl humaninsulin; B29-N-palmitoyl human insulin; B28-N-myristoyl LysB28ProB29human insulin; B28-N-palmitoyl-LysB28ProB29 human insulin;B30-N-myristoyl-ThrB29LysB30 human insulin; B30-N-palmitoyl-ThrB29LysB30human insulin; B29-N-(N-palmitoyl-Y-glutamyl)-des(B30) human insulin;B29-N-(N-lithocholyl-Y-glutamyl)-des(B30) human insulin;B29-N-(ω-carboxyheptadecanoyl)-des(B30) human insulin andB29-N-(ω-carboxyheptadecanoyl) human insulin.

Exendin-4 for example means Exendin-4(1-39), a peptide of the sequenceH-His-Gly-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Leu-Ser-Lys-Gln-Met-Glu-Glu-Glu-Ala-Val-Arg-Leu-Phe-Ile-Glu-Trp-Leu-Lys-Asn-Gly-Gly-Pro-Ser-Ser-Gly-Ala-Pro-Pro-Pro-Ser-NH2.

Exendin-4 derivatives are for example selected from the following listof compounds:

H-(Lys)4-des Pro36, des Pro37 Exendin-4(1-39)-NH2,

H-(Lys)5-des Pro36, des Pro37 Exendin-4(1-39)-NH2,

des Pro36 Exendin-4(1-39),

des Pro36 [Asp28] Exendin-4(1-39),

des Pro36 [IsoAsp28] Exendin-4(1-39),

des Pro36 [Met(O)14, Asp28] Exendin-4(1-39),

des Pro36 [Met(O)14, IsoAsp28] Exendin-4(1-39),

des Pro36 [Trp(O2)25, Asp28] Exendin-4(1-39),

des Pro36 [Trp(O2)25, IsoAsp28] Exendin-4(1-39),

des Pro36 [Met(O)14 Trp(O2)25, Asp28] Exendin-4(1-39),

des Pro36 [Met(O)14 Trp(O2)25, IsoAsp28] Exendin-4(1-39); or

des Pro36 [Asp28] Exendin-4(1-39),

des Pro36 [IsoAsp28] Exendin-4(1-39),

des Pro36 [Met(O)14, Asp28] Exendin-4(1-39),

des Pro36 [Met(O)14, IsoAsp28] Exendin-4(1-39),

des Pro36 [Trp(O2)25, Asp28] Exendin-4(1-39),

des Pro36 [Trp(O2)25, IsoAsp28] Exendin-4(1-39),

des Pro36 [Met(O)14 Trp(O2)25, Asp28] Exendin-4(1-39),

des Pro36 [Met(O)14 Trp(O2)25, IsoAsp28] Exendin-4(1-39),

wherein the group -Lys6-NH2 may be bound to the C-terminus of theExendin-4 derivative;

or an Exendin-4 derivative of the sequence

des Pro36 Exendin-4(1-39)-Lys6-NH2 (AVE0010),

H-(Lys)6-des Pro36 [Asp28] Exendin-4(1-39)-Lys6-NH2,

des Asp28 Pro36, Pro37, Pro38Exendin-4(1-39)-NH2,

H-(Lys)6-des Pro36, Pro38 [Asp28] Exendin-4(1-39)-NH2,

H-Asn-(Glu)5des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1-39)-NH2,

des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-(Lys)6-des Pro36 [Trp(O2)25, Asp28] Exendin-4(1-39)-Lys6-NH2,

H-des Asp28 Pro36, Pro37, Pro38 [Trp(O2)25] Exendin-4(1-39)-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28] Exendin-4(1-39)-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28]Exendin-4(1-39)-NH2,

des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28]Exendin-4(1-39)-(Lys)6-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28]Exendin-4(1-39)-(Lys)6-NH2,

H-(Lys)6-des Pro36 [Met(O)14, Asp28] Exendin-4(1-39)-Lys6-NH2,

des Met(O)14 Asp28 Pro36, Pro37, Pro38 Exendin-4(1-39)-NH2,

H-(Lys)6-desPro36, Pro37, Pro38 [Met(O)14, Asp28] Exendin-4(1-39)-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Met(O)14, Asp28]Exendin-4(1-39)-NH2,

des Pro36, Pro37, Pro38 [Met(O)14, Asp28] Exendin-4(1-39)-(Lys)6-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Met(O)14, Asp28]Exendin-4(1-39)-(Lys)6-NH2,

H-Asn-(Glu)5 des Pro36, Pro37, Pro38 [Met(O)14, Asp28]Exendin-4(1-39)-(Lys)6-NH2,

H-Lys6-des Pro36 [Met(O)14, Trp(O2)25, Asp28] Exendin-4(1-39)-Lys6-NH2,

H-des Asp28 Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25]Exendin-4(1-39)-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Met(O)14, Asp28] Exendin-4(1-39)-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28]Exendin-4(1-39)-NH2,

des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28]Exendin-4(1-39)-(Lys)6-NH2,

H-(Lys)6-des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28]Exendin-4(S1-39)-(Lys)6-NH2,

H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28]Exendin-4(1-39)-(Lys)6-NH2;

or a pharmaceutically acceptable salt or solvate of any one of theafore-mentioned Exendin-4 derivative.

Hormones are for example hypophysis hormones or hypothalamus hormones orregulatory active peptides and their antagonists as listed in RoteListe, ed. 2008, Chapter 50, such as Gonadotropine (Follitropin,Lutropin, Choriongonadotropin, Menotropin), Somatropine (Somatropin),Desmopressin, Terlipressin, Gonadorelin, Triptorelin, Leuprorelin,Buserelin, Nafarelin, Goserelin.

A polysaccharide is for example a glucosaminoglycane, a hyaluronic acid,a heparin, a low molecular weight heparin or an ultra low molecularweight heparin or a derivative thereof, or a sulphated, e.g. apoly-sulphated form of the above-mentioned polysaccharides, and/or apharmaceutically acceptable salt thereof. An example of apharmaceutically acceptable salt of a poly-sulphated low molecularweight heparin is enoxaparin sodium.

Antibodies are globular plasma proteins (˜150 kDa) that are also knownas immunoglobulins which share a basic structure. As they have sugarchains added to amino acid residues, they are glycoproteins. The basicfunctional unit of each antibody is an immunoglobulin (Ig) monomer(containing only one Ig unit); secreted antibodies can also be dimericwith two Ig units as with IgA, tetrameric with four Ig units liketeleost fish IgM, or pentameric with five Ig units, like mammalian IgM.

The Ig monomer is a “Y”-shaped molecule that consists of fourpolypeptide chains; two identical heavy chains and two identical lightchains connected by disulfide bonds between cysteine residues. Eachheavy chain is about 440 amino acids long; each light chain is about 220amino acids long. Heavy and light chains each contain intrachaindisulfide bonds which stabilize their folding. Each chain is composed ofstructural domains called Ig domains. These domains contain about 70-110amino acids and are classified into different categories (for example,variable or V, and constant or C) according to their size and function.They have a characteristic immunoglobulin fold in which two β sheetscreate a “sandwich” shape, held together by interactions betweenconserved cysteines and other charged amino acids.

There are five types of mammalian Ig heavy chain denoted by α, δ, ε, γ,and μ. The type of heavy chain present defines the isotype of antibody;these chains are found in IgA, IgD, IgE, IgG, and IgM antibodies,respectively.

Distinct heavy chains differ in size and composition; α and γ containapproximately 450 amino acids and δ approximately 500 amino acids, whileμ and ε have approximately 550 amino acids. Each heavy chain has tworegions, the constant region (C_(H)) and the variable region (V_(H)). Inone species, the constant region is essentially identical in allantibodies of the same isotype, but differs in antibodies of differentisotypes. Heavy chains γ, α and δ have a constant region composed ofthree tandem Ig domains, and a hinge region for added flexibility; heavychains μ and ε have a constant region composed of four immunoglobulindomains. The variable region of the heavy chain differs in antibodiesproduced by different B cells, but is the same for all antibodiesproduced by a single B cell or B cell clone. The variable region of eachheavy chain is approximately 110 amino acids long and is composed of asingle Ig domain.

In mammals, there are two types of immunoglobulin light chain denoted byλ and κ. A light chain has two successive domains: one constant domain(CL) and one variable domain (VL). The approximate length of a lightchain is 211 to 217 amino acids. Each antibody contains two light chainsthat are always identical; only one type of light chain, κ or λ, ispresent per antibody in mammals.

Although the general structure of all antibodies is very similar, theunique property of a given antibody is determined by the variable (V)regions, as detailed above. More specifically, variable loops, threeeach the light (VL) and three on the heavy (VH) chain, are responsiblefor binding to the antigen, i.e. for its antigen specificity. Theseloops are referred to as the Complementarity Determining Regions (CDRs).Because CDRs from both VH and VL domains contribute to theantigen-binding site, it is the combination of the heavy and the lightchains, and not either alone, that determines the final antigenspecificity.

An “antibody fragment” contains at least one antigen binding fragment asdefined above, and exhibits essentially the same function andspecificity as the complete antibody of which the fragment is derivedfrom. Limited proteolytic digestion with papain cleaves the Ig prototypeinto three fragments. Two identical amino terminal fragments, eachcontaining one entire L chain and about half an H chain, are the antigenbinding fragments (Fab). The third fragment, similar in size butcontaining the carboxyl terminal half of both heavy chains with theirinterchain disulfide bond, is the crystalizable fragment (Fc). The Fccontains carbohydrates, complement-binding, and FcR-binding sites.Limited pepsin digestion yields a single F(ab′)2 fragment containingboth Fab pieces and the hinge region, including the H-H interchaindisulfide bond. F(ab′)2 is divalent for antigen binding. The disulfidebond of F(ab′)2 may be cleaved in order to obtain Fab'. Moreover, thevariable regions of the heavy and light chains can be fused together toform a single chain variable fragment (scFv).

Pharmaceutically acceptable salts are for example acid addition saltsand basic salts. Acid addition salts are e.g. HCl or HBr salts. Basicsalts are e.g. salts having a cation selected from alkali or alkaline,e.g. Na+, or K+, or Ca2+, or an ammonium ion N+(R1)(R2)(R3)(R4), whereinR1 to R4 independently of each other mean: hydrogen, an optionallysubstituted C1-C6-alkyl group, an optionally substituted C2-C6-alkenylgroup, an optionally substituted C6-C10-aryl group, or an optionallysubstituted C6-C10-heteroaryl group. Further examples ofpharmaceutically acceptable salts are described in “Remington'sPharmaceutical Sciences” 17. ed. Alfonso R. Gennaro (Ed.), MarkPublishing Company, Easton, Pa., U.S.A., 1985 and in Encyclopedia ofPharmaceutical Technology.

Pharmaceutically acceptable solvates are for example hydrates.

Further scope of applicability of the present invention will becomeapparent from the detailed description given hereinafter. However, itshould be understood that the detailed description and specificexamples, while indicating preferred embodiments of the invention, aregiven by way of illustration only, since various changes andmodifications within the spirit and scope of the invention will becomeapparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description given hereinbelow and the accompanying drawingswhich are given by way of illustration only, and thus, are not limitiveof the present invention, and wherein:

FIG. 1 shows an exemplary embodiment of a medicament delivery device andcartridge according to the present invention,

FIG. 2 shows another exemplary embodiment of a medicament deliverydevice and cartridge according to the present invention; and

FIG. 3 shows a logical view of a medicament delivery device andcartridge according to the present invention.

Corresponding parts are marked with the same reference symbols in allfigures.

DETAILED DESCRIPTION

FIG. 1 shows an exemplary embodiment of a medicament delivery device 100and cartridge 200 according to the present invention. The deliverydevice 100 may be any type of injection device which is used to inject amedicament from a syringe or cartridge. Those of skill in the art willunderstand that such injection devices include, but are not limited to,pen injectors, pre-filled syringes, autoinjectors, perfusion devices,infusion devices, etc. Further, the medicament delivery device 100according to the present invention may be embodied as an attachment to apre-existing injection device. For example, the delivery device 100 maybe a cap-type attachment which is removably coupled to an injectiondevice and can be reused.

In the exemplary embodiment, the delivery device 100 may includecomponents common to conventional delivery devices such as, for example,one or more springs, plungers, needle shields, syringe/cartridgecarriers, etc.

In the exemplary embodiment shown in FIG. 1, the delivery device 100includes an optical system 105 comprising a first receiver 110 and asecond receiver 115. In the exemplary embodiment, the receivers 110, 115are photodiodes, phototransistors, photomulipliers, etc. capable ofreceiving an optical signal (e.g., light) and converting the opticalsignal into an electrical signal. In the exemplary embodiment, thereceivers 110, 115 are arranged in parallel in the delivery device 100and are spaced apart axially by an axial offset A and radially by aradial offset R from a longitudinal axis L of the delivery device 100.While the exemplary embodiment depicts only two receivers, those ofskill in the art will understand that more than two receivers may beutilized.

The exemplary embodiment of the cartridge 200 shown in FIG. 1 includes abody 205 containing a medicament M and a bung 210 slidably disposed inthe body 205. The bung 210 has a distal face 215 in contact with themedicament M and a proximal face 220. In an exemplary embodiment, alight element 225 is coupled to the cartridge 200. For example, thelight element 225 may be coupled to the proximal face 220 of the bung210, e.g., embedded wholly or partially in the bung 210 or disposed onthe proximal face 220 (e.g., via an adhesive, clamping or welding). Inanother exemplary embodiment, the light element 225 may be disposed onthe body 205. In other exemplary embodiments, more than one lightelement 225 may be disposed on the cartridge 200, and in the case of aplurality of light elements 225, each light element 225 may emit adifferent wavelength of light. In a further exemplary embodiment, thelight element 225 may be disposed on a component (e.g., a carrier) whichis coupled to the cartridge 200. For example, the cartridge 200 may beplaced in a carrier which is slidably disposed in the delivery device100. Thus, movement of the carrier may correspond directly to movementof the cartridge 200.

In the exemplary embodiment shown in FIG. 1, the light element 225 is alight emitting device, e.g., a light emitting diode (LED). In theexemplary embodiment shown in FIG. 2, the light element 225 is a lightreflecting device, e.g., a mirror. In the embodiment shown in FIG. 2, alight source 230 may be disposed on the delivery device 100 and focusedtoward the light element 225. For example, the light source 230 may bepositioned between the receivers 110, 115. One or more reflectors orlenses may be positioned adjacent the light element 225 to focus and/ordirect light emitting from the light element 225. If the light element225 requires a power source (not shown) such as a battery, it may beelectrically, inductively or radio frequency coupled to the lightelement 225.

As explained further herein, displacement and direction of displacementof the bung 215 and/or the cartridge 200 may be determined by analyzingthe optical signals from the light element 225 which are received by thereceivers 110, 115.

FIG. 3 shows a logical view of an exemplary embodiment of a medicamentdelivery device and cartridge according to the present invention. Asnoted above, the receivers 110, 115 are spaced apart axially by an axialoffset A and radially by a radial offset R from the longitudinal axis Lof the delivery device 100. A reference line R_(min) is designed to be amost proximal position (e.g., pre-use position) of the light element 225in the delivery device 100, and a first minimum axial distance r1between the light element 225 and the first receiver 110 and a secondminimum axial distance r2 between the light element 225 and the secondreceiver 115. A displacement r of the light element 225 away from thereference line R_(min) can be determined by analyzing the opticalsignals received by the receivers 110, 115. The displacement r may thenbe utilized by, for example, a controller in the delivery device 100 tocomputer an amount of the medicament delivered, to operate othermechanisms (e.g., user interface, feedback, needle safety, etc.) of thedelivery device 100.

In an exemplary embodiment, the controller in the delivery device 100may utilize the following formulas to compute illumination values ateach of the receivers 110, 115 to determine the displacement r.

A luminance intensity dispersion formula (1) shown below solves for anillumination value E (in lux) which corresponds to the specificillumination value received at each of the receivers 110, 115. Formula(1) is discussed in Kuchling, H., “Taschenbuch der Physik,” Carl HanserVerlag, 2004, which is incorporated by reference herein.

$\begin{matrix}{{E = {\frac{1*\cos \; \alpha}{r^{2}}E{\text{:}\mspace{14mu}\lbrack{lx}\rbrack}}};{I{\text{:}\mspace{14mu}\lbrack{cd}\rbrack}};{r{\text{:}\mspace{14mu}\lbrack m\rbrack}}} & (1)\end{matrix}$

To solve for the illumination values E1 and E2 at the first receiver 110and the second receiver 115, respectively, the following formulas can beused:

$\begin{matrix}{E_{1} = \frac{1*\cos \; \alpha}{\left( {r + r_{1}} \right)^{2}}} & (2) \\{E_{2} = \frac{1*\cos \; \alpha}{\left( {r + r_{2}} \right)^{2}}} & (3)\end{matrix}$

where E1 illumination value at first receiver 110

-   -   E2 illumination value at second receiver 115    -   I total illumination    -   α angle of diffusion of light from the light element 225        relative to the longitudinal axis L    -   r displacement of light element 225 relative to the reference        line R_(min)    -   r1 first minimum axial distance r1 between the light element 225        and the first receiver 110 (e.g., when the light element 225 is        positioned at the reference line R_(min))

Both formulas can be transformed to solve for the displacement r:

$\begin{matrix}{\frac{E_{1}}{I*\cos \; \alpha} = \frac{1}{\left( {r + r_{1}} \right)^{2}}} & (4) \\{\frac{I*\cos \; \alpha}{E_{1}} = \left( {r + r_{1}} \right)^{2}} & (5) \\{\sqrt{\frac{I*\cos \; \alpha}{E_{1}}} = {r + r_{1}}} & (6) \\{{\sqrt{\frac{I*\cos \; \alpha}{E_{1}}} - r_{1}} = r} & (7) \\{\frac{E_{2}}{I*\cos \; \alpha} = \frac{1}{\left( {r + r_{2}} \right)^{2}}} & (8) \\{\frac{I*\cos \; \alpha}{E_{2}} = \left( {r + r_{2}} \right)^{2}} & (9) \\{\sqrt{\frac{I*\cos \; \alpha}{E_{2}}} = {r + r_{2}}} & (10) \\{{\sqrt{\frac{I*\cos \; \alpha}{E_{2}}} - r_{2}} = r} & (11)\end{matrix}$

Both formulas can be used to solve for the total illumination I:

$\begin{matrix}{{\sqrt{\frac{I*\cos \; \alpha}{E_{1}}} - r_{1}} = {\sqrt{\frac{I*\cos \; \alpha}{E_{2}}} - r_{2}}} & (12) \\{{\sqrt{\frac{I*\cos \; \alpha}{E_{1}}} - \sqrt{\frac{I*\cos \; \alpha}{E_{2}}}} = {r_{1} - r_{2}}} & (13) \\{{\sqrt{I}*\left( {\sqrt{\frac{\cos \; \alpha}{E_{1}}} - \sqrt{\frac{\cos \; \alpha}{E_{2}}}} \right)} = {r_{1} - r_{2}}} & (14) \\{\sqrt{I} = \frac{r_{1} - r_{2}}{\left( {\sqrt{\frac{\cos \; \alpha}{E_{1}}} - \sqrt{\frac{\cos \; \alpha}{E_{2}}}} \right)}} & (15) \\{I = \left\lbrack \frac{r_{1} - r_{2}}{\left( {\sqrt{\frac{\cos \; \alpha}{E_{1}}} - \sqrt{\frac{\cos \; \alpha}{E_{2}}}} \right)} \right\rbrack^{2}} & (16)\end{matrix}$

Formula (16) describes a differential measurement based on the recordedintensity by each receiver 110, 115. The total illumination I can thenbe used to solve for the displacement r:

$\begin{matrix}{E_{1} = \frac{I*\cos \; \alpha}{r^{2}}} & (18) \\{r^{2} = \frac{I*\cos \; \alpha}{E_{1}}} & (19) \\{r = \sqrt{\frac{I*\cos \; \alpha}{E_{1}}}} & (20)\end{matrix}$

When the light element 225 is coupled to the bung 210, based on thedisplacement r, the controller can, for example, determine a dose of themedicament delivered, activate a safety mechanism (e.g., a needleshield), activate a user feedback mechanism (e.g., audible, tactile,visual), etc.

When the light element 225 is coupled to the body 205, based on thedisplacement r, the controller can, for example, determine a position ofa needle (e.g., needle penetration depth, needle retraction), activate asafety mechanism (e.g., a needle shield), activate a user feedbackmechanism (e.g., audible, tactile, visual), etc.

Those of skill in the art will understand that modifications (additionsand/or removals) of various components of the apparatuses, methodsand/or systems and embodiments described herein may be made withoutdeparting from the full scope and spirit of the present invention, whichencompass such modifications and any and all equivalents thereof.

1. A cartridge (200), comprising: a body (205) adapted to contain amedicament; a bung (210) slidably disposed in the body (205), the bung(210) having a distal face (215) and a proximal face (220); and a lightelement (225) coupled to a component of the cartridge (200).
 2. Thecartridge (200) according to claim 1, wherein the light element (225) iscoupled to the proximal face (220) of the bung (210).
 3. The cartridge(200) according to claim 2, wherein the light element (225) is wholly orpartially embedded in the bung (210).
 4. The cartridge (200) accordingto claim 1, wherein the light element (225) is coupled to the body(205).
 5. The cartridge (200) according to any of the preceding claims,further comprising: a power source electrically, inductively or radiofrequency coupled to the light element (225).
 6. The cartridge (200)according to any of the preceding claims, wherein the light element(225) is a light emitting device or a light reflecting device.
 7. Thecartridge (200) according to any of the preceding claims, wherein thebung (210) is translucent.
 8. The cartridge (200) according to any ofthe preceding claims, further comprising: a lens disposed adjacent thelight element (225).
 9. A medicament delivery device (100), comprising:a cartridge (200) according to any of claims 1-8; a first receiver (110)adapted to receive an optical signal from the light element (225) andconvert the optical signal into a first electrical signal; and a secondreceiver (115) adapted to receive an optical signal from the lightelement (225) and convert the optical signal into a second electricalsignal.
 10. The medicament delivery device (100) according to claim 9,further comprising: a light source (230) disposed adjacent the firstreceiver (110) and the second receiver (115), the light source (230)adapted to emit light toward the light element (225).
 11. The medicamentdelivery device (100) according to any of claims 9-10, wherein the firstreceiver (110) and the second receiver (115) are radially offset by aradial distance (R) from a longitudinal axis (L) of the delivery device(100).
 12. The medicament delivery device (100) according to any ofclaims 9-11, wherein the first receiver (110) and the second receiver(115) are axially offset by an axial distance (A).
 13. The medicamentdelivery device (100) according to any of claims 9-12, wherein the firstreceiver (110) is arranged a first minimum axial distance (r1) from areference line (R_(min)) and the second receiver (115) is arranged asecond minimum axial distance (r2) from the reference line (R_(min)).14. The medicament delivery device (100) according to claim 13, whereinthe reference line (R_(min)) corresponds to an axial position of thelight element (225) prior to use of the medicament delivery device(100).
 15. The medicament delivery device (100) according to any ofclaims 8-14, further comprising: a controller adapted to compute adisplacement (r) of the light element (225) relative to the referenceline (R_(min)) using the first and second electrical signals.
 16. Themedicament delivery device (100) according to claim 15, wherein thecontroller is adapted to compute a dose of medicament delivered or aneedle position based on the displacement (r).
 17. The medicamentdelivery device (100) according to claim 15, wherein the controllercomputes the displacement (r) as follows:$I = \left\lbrack \frac{r_{1} - r_{2}}{\left( {\sqrt{\frac{\cos \; \alpha}{E_{1}}} - \sqrt{\frac{\cos \; \alpha}{E_{2}}}} \right)} \right\rbrack^{2}$$r = \sqrt{\frac{I*\cos \; \alpha}{E_{1}}}$ where E1 illuminationvalue at first receiver 110; E2 illumination value at second receiver115; I total illumination; α angle of diffusion of light from the lightelement 225 relative to the longitudinal axis L; r displacement of lightelement 225 relative to the reference line R_(min); r1 first minimumaxial distance r1 between the light element 225 and the first receiver110 when the light element 225 is positioned at the reference lineR_(min); and r2 second minimum axial distance r2 between the lightelement 225 and the second receiver 115 when the light element 225 ispositioned at the reference line R_(min).